ctDNA May Predict Early Response to Radiation of Gynecologic Cancers

How to Use It?

Invited discussant Casey M. Cosgrove, MD, a gynecologic oncologist at Ohio State University Comprehensive Cancer Centers facility in Hilliard, Ohio, said that the reduction of ctDNA levels in all patients was “great,” but the question remains about how the information from ctDNA might be used to guide care in patients undergoing radiation therapy.

“The main questions I have are: If I don’t clear the ctDNA do I need to do more therapy? If I do clear does that mean I need to do less therapy? And if I have negative ctDNA to start what do I do?” he said.

The answers will be found only with further prospective studies, he emphasized.

“These technologies are only going to get better, and better, and better, and this is going to be a conversation that our patients are going to be bringing up, and this is going to be technology that we’re going to be using in our clinics in the very near future,” he added.

Session comoderator Michael Bookman, MD, a gynecology oncologist at Kaiser Permanente in San Francisco, said “it’s worth remembering that FDA approval of a diagnostic test can be obtained prior to showing any clinical benefit. So these are tests that measure what they say they’re measuring, but they haven’t been validated as improving clinical outcomes, which is the task that clearly lies ahead of us.”

The study was internally funded. Dr. Wernicke reported no relevant disclosures. Dr. Cosgrove reported a consulting or advisory role for Intuitive Ltd., GlaxoSmithKline, AstraZeneca, ImmunoGen, and Merck, and research fees from GSK. Dr. Bookman reported clinical trial advising/monitoring for Immunogen and Clovis Oncology, with fees paid to his institution.